Improvement in manufacture of flanges for sheet-metal covers



JAMES FALLOWS.

Manilfacture of Flanges for Sheet Metal Covers.

Patented Feb. 6,1872. F1 .1.

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WiTNESSES:

:INVENTOR M I g c/ /7 AILPHOI'D-UI'IIOGRIFHIC ca n x (mean/5.? mums.)

IT STATES ATE T FFICE.

JAMES FALLOWS, OF PHILADELPHIA, PENNSYLVANIA.

Specification forming part of Letters Patent No. 123,339, dated February 6, 1872.

Specification describing certain Improvements in the Manufacture of Tapering Flanges for Sheet-Metal Covers, invented by JAMES FALLOWS, of the city of Philadelphia, in the State of Pennsylvania.

In the production of the tapering flanges required in the construction of sheet-metal covers, whereby they are adapted to flt readily into the months or collars of sheet-metal vessels, it has heretofore been necessary to cut the strips of which they are made in a curved form out of a plate of sheet metal, and, consequently, at a considerable loss of the sheet by waste.

My invention relates to the production of the said tapering flanges by cutting the strips out with straight parallel edges, and then givin them the curve required to produce the tapering flange by a series of equidistant tapering indentations of uniform size, extending nearly across one side of the strip, at right angles from an extreme side edge of the same, toward the opposite side edge, as will hereinafter he more fully explained; the object of my invention being the production of tapering flanges for sheet-metal covers or lids, with greater facility and accuracy, and without causing any waste in the sheet-metal plate out of whic the strips are cut.

Fi gnre 1 represents the straight strip of sheet metal as cut from the large sheet. Fig. 2 represents the same plate after it has been indented aud curved to produce the required taper in the flange. Fig. 3 represents the indented and curved strip bent into a ring to form the flange, and with the edge of the larger diameter of the said ring turned outward to receive upon it the usual overlapping edge of the top plate of the lid, as represented in Fig. 4, which shows the flange applied.

As the strip A (see Fig. 1) has straight parallel side edges, it will be seen that it can be cut out of a sheet-metal plate without causing any waste. It will also be understood that if said plate be indented on one side by a series of transverse equidistant tapering indenta tions, at a, (see Fig. 2,) across from one side edge about threetourths, more or less, of the width of the said strip A, it will be curved as is shown in the figure. The indentations a a, are readily produced by passing the strip, Fig. 1, between two hardened steel rolls, say, one and one-half inches in diameter, the upper one of which having teeth, the faces of which being of the tapering form required, and the lower one having a plain surface. After the strip has been passed between the indentingrolls, it is bent into a ring by bringing its two ends a a to lap past each other to form the flange, and then the edge a, at its larger diameter, turned outward, whereby the flange can be retained by the usual overlap of the outer edge of the top plate B of the cover, in the usual manner. See Fig. 4.) These flanges are intended to be formed up, as shown in Fig. 3, and put on sale to the trade Without soldering together their lapping ends a a.

I claim as my invention As a new article of manufacture for sheetmetal covers, a tapering flange of sheet metal constructed out of a straight-cut strip of sheet metal, and curved by indentations, substantially in the manner described and set forth.

Witnesses: JAMES FALLOWS.

BENJ. MORISON, WM. H. MoRIsoN. 

